Railway lighting system



L. A. WATSON.

RAILWAY LIGHTING SYSTEM.

APPLiCATlON FILED JAN. 29, 1916.

1,417,787. Patented May30, 1922.

IN VEN TOR WITNESSES Arm/mars UNITED STATES PATENT ()FFICE.

LEONARD A. WATSON. OF PORT WASHINGTON. NEW YORK, ASSIGNOR TO THE SAFETYCAR HEATING- .AND LIGHTING COMPANY, OF NEW NEW JERSEY.

YORK, N. Y., A CORPORATION OF RAILWAY LIGHTING SYSTEM.

Specification of Letters Patent. Patented )[ay 1922 Application filedJanuary 29. 1916. Serial No. 74,999.

To all whom it may concern:

Be it known that I. LEONARD A. \VA'rsoN, a citizen of the l'nitedStates. residing at Port 'ashington, L. I.. in the county of Nassau andState of New York, have .invented certain new and useful Improvements inRailway Lighting Systems. of which the following is a full, clear. andexact description. such as will enable others skilled in the art towhich it appertains to make and use the same.

This invention relates to railway lighting systems. and moreparticularly to the automatic regulation of axle driven car lightinggenerators employed to supply current to a translating lamp circuit andto a storage battery associated in the system as a reservoir of currentto supply the lamps when, for example, the train speed is below thatatwhich the generator is designed to carry the load.

One of the objects of the invention is to provide simplified andimproved controlling means to govern the generator in accordance withthe state of battery charge.

Further objects are to simplify the character of the generatorcontroller, to reduce the factors employed in the control, and toprovide reliable protection and operation of the various elements of thesystem at all times.

Other objects will be in part obvious and in part noted hereinafter inconnection with the description of the accompanying drawing. whichillustrates diagrammatically an exemplary embodiment of the invention.

It is customary in car lighting systems to provide a generator driven bythe car axle and having a shunt field winding with a regulatingresistance in the field circuit, together with an automatic switch inthe main circuit designed to connect the generator with the load whenthe voltage of the generator attains a value for eflicient currentdelivery.

In the drawing there is shown a generator G having a shunt field F witha carbon pile resistance C serially included in the field circuit. Thecarbon pile is of a character to vary its resistance in accordance withthe variation in pressure of the contacting carbons, which pressure isgoverned by a bell crank lever 1 pivoted and normally biased either by aspring or by gravity to compress the carbons to a minimum resistancevalue.

A main switch 2 is positioned in one of the lines between the generatorand the battery and is automatically controlled by a shunt coll thestrength of which insures an open circuit when the train speed is belowa predetermined rate, for example, fifteen miles an hour. A battery Band lamps L are connected in parallel circuits across the generatormains 4 and 5.

A voltage coil 6, comprising the winding of a solenoid having a magneticcore 7 attached to the long arm of the bell crank lever 1, constitutesthe electro-magnetic controlling means for effecting the generatorregulation. This coil 6 is connected by line 8 to one generator main andthrough adjustable resistance R arranged in steps 9 and 10 by line 11 tothe other generator main. An ampere hour meter M or other mechanismwhich uantitatively measures the charge and disc large of current to orfrom the bat tery. or other suitable electro-mechanical or electricaldevice which is affected by condition of the battery with respect to theavailable stored current therein, is employed to control the resistanceR in the circuit of the voltage coil in such manner as to alter thesetting of the latter in accordance with the condition of the batterycharge, and accordingly to determine the degree of responsiveness of thevoltage coil and voltage of the generator to be maintained. By thusaltering the resistance in the circuit of coil 6 the 7 effectiveresistance per mean turn of the coil is altered and the number of ampereturns for a given voltage is changed.- For example. with increasedeffective resistance per mean turn a higher voltage is required torestore the pull of the coil to normal.

The meter M may be provided with a suitable armature and with a fieldwinding MF in the battery circuit so connected that the current to thebattery operates the meter in one direction, and current from thebattery operates the meter in the reverse direction. lVhile thegenerator is supplying current to the battery and lamps simultaneously,it will be noted that the meter operates in response only to thatportion of the current delivered to the battery. I

'hen a generator controlled only to de liver current at constant voltageis employed to charge a storage battery, there tends to result aninjurious initial inrush of current if the battery is depleted, and thecurrent tends thereafter to taper during the charge for inherentprotection of the battery against over-charge. In order to prevent suchinjurious inrush of current and to regulate more e'fliciently thecharging rate, there is provided an element of resistance 13 in serieswith the battery circuit when the battery is largely discharged, whichresistance tends to limit the amperageof the current traversing thecircuit and thereby to limit the initial inrush to the battery.

The meter M is also provided with suitable contacts, illustratedschematically, whereby suitable circuits are established by the movablemeter pointer l t in accordance with its position indicative of theinstant battery charge. pointer is provided with a contact 15 and aseparate insulated contact 16, the former of which engages with asegmental contact 17 while the condition of the battery charge is belowa predetermined point. During this condition there is a circuitestablished across the contacts 15 and'17 extending from the voltagecoil 6 by line 13 through the meter by line 19 to the opposite side ofthe resistance R, thereby shunting said resistance and rendering thevoltage coil 6 of maximum responsiveness, for example to maintain volts.During an initial portion of this time the battery resistance 13 isincluded in circuit so thatthei effect of this resistance in addition tothe setting of the voltage coil insures proper charging rate to thebattery.

After the meter has operated to indicate that the battery has becomepartially charged. the pointer contact 16 engages the segmental metercontact 20 and establishes a shunt cir cuit thereacross about thebattery resistance 13, so that thereafter all of the voltage of thegenerator is applied to the battery. After (or before or simultaneouslywith, as desired) this removal of the battery resistance, the pointercontact 15 travels to leave the meter contact 17 and engages a secondsegmental contact 21, which restores section 10 of the resistanceR incircuit with the voltage coil, but still short-circuits section 9 ofsuch resistance. Under these conditions the setting of the voltage coilis altered toa lesser degree of responsiveness, for example to maintain40 volts. As the battery reaches fully charged condition the metercontact 15 is moved further to leave contact 21 and engages a thirdcontact 22, which again short-circuits all the resistance. R from thecircuit of the voltage coil, thereby again altering its setting to 35volts or floating battery value. The voltage of the battery has thenrisen to a point where the charging current is automatically reduced tosafe confines. If desired, however, the pointer contact 16 may bearranged (as shown) to leave engagement with the meter contact 20 atthis time and thus reinsert battery resistance As illustrated, themetercircuits described.

'quence of t load.

During discharge of the battery, whenthe train is at rest or belowcritical speed, the meter travels backward to reverse the sequence ofcircuits set forth, and insure the proper character of generator controlwhen the generator resumes action. In order to prevent uselessconsumption of current by the battery resistance 13 when the battery issupplying current to the lamps. there are provided back contacts 23 onthe main switch 2 connected to a shunt circuit by lines 24 and 25 to cutout the battery resistance when the main switch is opened. This is inaddition to the battery resistance shunt circuit established by themeter contacts within narrower limits between full and depleted battery.

The meter M is shown schematically as cstablishing direct contact by itsmovable pointer and contact segments for the various It will beunderstood. however, that the meter may be constructed as desired,either to make and break circuit directly, or through the medium ofsuitable telegraphic relays, in order to reduce the value of thecurrents controlled by the meter pointer. It will further be understoodthat the meter is provided with resetting means to establish synchronismwith the state of battery charge. and also with automatic. means tocompensate for internal battery lomes.

The voltage coil 6 is permanently connected in circuit to effect theregulation throughout the operation of the system, the character of theregulation being automatically proportioned to the condition of thebattery charge. In case of breakage of a battery lead, it will furtherbe seen that the voltage control is still maintained to govern thegenerator. The sections 9 and 10 of the resist ance R of the circuit ofthe voltage coil may be ad'ustable, and the time, and see shunt circuitsabout these resistance sections may be altered as desired by mechanicalalteration of the meter.

Having described my invention. what I claim as new and desire to secureby Letters Patent is:

1. In a railway car lighting system. in combination; a variable speedgenerator: a storage battery connected to be charged thereby;regulating'means, responsive to a function of the generator output.operable to maintain the generator voltage constant: and meansresponsive to the condition of charge of the battery arranged to affectsaid regulating means to maintain a higher constant generator voltagewhen the battery has I reached a predetermined state of charge.

2. In a railway car lighting system in combination; a variable speedgenerator; a

storage battery connected to be charged.

an ampere hour meter constructed and connected to substantiallysynchronize with the quantity of battery charge, a resistance con nectedin' the battery circuit adapted to limit the charging current, andconnections whereby said resistance is rendered relatively moreeffective by said meter during predetermined initial battery char ingand relatively less effective during a su sequent period of batterycharging.

4. In a railway car lighting system, in combination, a variable speedgenerator, a storage battery adapted for connection therewith, an amperehour meter constructed and connected to substantially synchronize withthe quantity of battery charge, means in the battery circuit adapted tolimit the charging current, and connections whereby said means iscontrolled by said meter and is rendered relatively more eflective bythe latter at the beginning and end of battery charging and relativelyless efiective during an intermediate period of battery charging. 1

5. In a railway car lighting system, in combination, a variable speedgenerator having a shunt field, a storage battery adapted for connectionacross the generator mains, an ampere hour meter constructed andconnected to substantially synchronize with the quantity of batterycharge, a resistance connected in the battery circuit adapted to limitthe charging current, and connections whereby said resistance isrendered effective by said meter at the beginning and end of batb terycharging and is rendered ineffective by said meter during anintermediate period of charging.

6. In a railway car lighting system, in combination, a variable speedgenerator, voltage responsive means to regulate said generator whilerunning above a predetermined speed, a storage battery adapted forconnection with said generator, means operable by the battery chargingand discharging current to substantially synchronize with the .latingmeans to depress the generator quantity of battery charge, a fixedresistance in the battery circuit to limit the charging current andconnections whereby said resistance is rendered effective by saidsecondmentioned means during a predetermined initial period of batterycharging to depress the charging current at the maintained generatorvoltage.

7. In a railway car lighting system, in combination, a variable speedgenerator, regulating means therefor, a storage battery adapted forconnection with said generator, and automatic means for causing saidreguvoltage to one standard of constancy during a predetermined initialperiod of charging and to raise the generator voltage to anotherstandard of constancy during a subsequent predetermined period ofcharging.

8. In a railway carlighting system, in'

combination, a variable speed generator, regulating means therefor, astorage battery adapted for connection with said generator, automaticmeans for causing said regulating means to depress the generator voltageduring an initial period of charging, to restore full voltage duringanother period of charging and again to depress the voltage at the endof charging.

9. In a railway car lighting system, in combination, a variable speedgenerator, voltage responsive regulating means therefor, a storagebattery adapted for connection with said generator, means operable bythe battery charging and discharging current and substantiallysynchronizing with the quantity of battery charge, and means controlledby said second-mentioned means and controlling said first-mentionedmeans to depress the generator voltage to one standard of constancyduring a predetermined initial period of batterycharging and to raisethe generator voltage to another standard of constancy during-asubsequent predetermined period of battery charging.

10. In arailway car lighting system, in combination, a variable speedgenerator, voltage responsive regulating means therefor, a storagebattery adapted for connection with said generator, means operable bythe battery charging and discharging current and substantiallysynchronizing with the quantity of battery charge, and means controlledy said second-mentioned means and controlling said first-mentioned meansto depress the generator voltage during a predetermined initial periodof battery charging. to restore full voltage during a predeterminedsubsequent period of battery charging, and again to depress the voltagewhen the charge is complete. 7 11. In arailway car lighting system, incombination, a variable speed generator, a storage battery adapted forconnection therewith, and automatic regulating means responsive to afunction of the generator output and to the condition of charge of thebattery adapted to maintain one generator voltage constancy during aninitial pe riod of battery charging and another higher generator voltageconstancy during a subsequent period of battery charging.

12. In a railway car lighting system, in combination, a variable speedgenerator, a storage battery adapted for connection therewith,andautomatic regulating means to maintain a depressed generator voltageconstancy during an initial period of battery charging, age constancyduring a subsequent period of battery charging, and a depressedgenerator voltage constancy at the end of battery charging.

' generator mains; means adapted to limit the 13. In a railway carlighting system, in

combination, a variable speed generator; a

storage battery adapted for connectiontherewith; voltage responsiveregulating means for said generator; and means, including an ampere hourmeter adapted to substantially synchronize with the quantity of batterycharge, whereby said regulating means maintains one predeterminedgenerator voltage constancy during a predetermined initial period ofbattery charging and another higher predetermined voltage constancyduring'a. subsequent period of battery charging.

14. The herein described method of controlling an-electric car lightingsystem including a variable speed generator and a battery, whichconsists in maintaining a depressed generator voltage constancy duringan initial period of battery charging and thereafter in maintaining anincreased generator voltage constancy until the battery charge iscompleted. V

15. In a railwayscar lighting system, in combination, a variable speedgenerator; automatic regulating means therefor; a storage batteryadapted for connection across the generator mains; means, independent ofsaid regulating means, adapted to affect the battery charging current;and common means for governing the action of said firstmentioned meansand said second-mentioned means.

16. In a railway car lighting'system, in combination, a variable speedgenerator; automatic regulating means therefor; a storage batteryadapted for connection across the battery charging current independentlyof said regulating means; and means, includmg an ampere hour meterconstructed and connected to substantially synchronize with an incr asedgenerator volt-- the quantity of battery charge, to determine thecharacter of regulation to be effected by said regulating means and togovern the effectiveness of said second mentioned means.

17. In a railway car lighting system, in

combination, a variable speed shunt Wound generator, voltage responsiveregulating -ing a voltage coil connected across the generator mains; astorage battery adapted for connection across the generator mains; aresistance connected in the battery circuit to limit the chargingcurrent; means to vary the resistance per mean turn of said voltagecoil; and means controlling said last-mentioned means and said batterycircuit resistance to decrease the resistance per mean turn of saidvoltage coil and render said battery circuit resistance efi'ective atthe beginning of charge, and to increase the resistance per mean turn ofsaid voltage coil and render said battery circuit resistance ineffectiveduring a subsequent period of battery charge.

19. The herein described method of controlling car lighting systemswhich consists in positively limiting the initial charging current tothe battery. when depleted, substantially independently of the generatorregulation and thereafter governing the charging current solely byregulating the generator voltage.

stant in spite of speed changes, and means automatically operative at aninterval during the period from low to full battery charge andindicative only of battery conditions for establishing the standard ofregulation to be maintained by said regulator for a succeeding period ofcharge prior to full battery charge. I

In testimony whereof I aflix my signature, in the presence of a witness.

LEONARD A. \VATSON. lVit-ness:

C. J. KULBBRG.

